From the EP 1 807 624 B1, a rotary displacement pump is known which allows for pumping flowable, relatively viscose materials in the food stuff industry, the chemical and biochemical industry, the medical industry and the cosmetic industry. Examples of materials that can be pumped by such rotary displacement pump are yoghurt, soup, sauce, mayonnaise, fruit juice, cheese material, chocolate, paint, cosmetic cream, and lipstick material.
Now there is a need for pumping solids emulsions, especially liquid explosives. Such liquid explosives are for example used in the mining industry in the field of tunneling and operation of quarry where such liquid explosives have to be pumped in cavities and channels in the rocks where they are ignited to explode in a controlled fashion.
The rotary displacement pump disclosed in the EP 1 807 624 B1 is not suitable for pumping such solids emulsions. When pumping such solids emulsions with the displacement rotary pump, the solids emulsions collect, build up and pack in certain regions of the pump which increases the friction, builds up additional pressure and heats up the pump. This results in a loss of efficiency or even a total outage of the pump. When pumping liquid explosives comprising small spherical components also referred to as prill it is this prill that collects, builts up and packs in many places of that pump, which in addition to the drawbacks as mentioned above, is dangerous to men and environment. In the worst case, the whole rotary displacement pump can explode, when the temperature within the pump rises above a critical point.
Currently, the pumps used for pumping such solids emulsions and liquid explosives are of bigger size and more complex design which makes their use in connection with solids emulsions and liquid explosives inconvenient and expensive and which limits the applications to situations where enough space is available for such bigger pumps.